Tuning control



D86. 1, 1931. R EATON ET AL 1,833,893

TUNING CONTROL Filed June 14, 1929 3 Sheets-Sheet 1 a 4- Dec. 1, 1931.EATON ET AL 1,833,893

TUNING CONTROL Yul/5277013 fags/55am Dec. 1, 1931 EATON ET AL 1,833,893

TUNING CONTROL Filed June 14, 1929 5 Sheets-Shet s n Q R h I w w N m a Ia; m h I r I E "I i #0 IN t a To: TR

x; R Jzzuszfiars: 8 @55557027 f'farrz'sfiose 1952 Patented Dec. 1, 1931UNITED STATES PATENT OFFICE j] GEORGE R. E ATON, OF OAK PARK,AND'MORRISROSE, OF CHICAGO, ILLINOIS, ASSIGNORS T KELLOG-G SWITGHBOARD &SUPPLY CO.,' OF CHICAGO, ILLINOIS, A. CORPORATION OF ILLINOIS I TUNINGCONTROL Application filed June 14, .1929. Serial No. 370,811. M 7

Our invention relates to the tuning of a multiple arrangement ofcouplers or trans formers such as are used in an inductively tuned radioreceiving circuit, and has to do more particularly with the tuning ofcouplers 0r transformers in which the inductance of the secondaries ofthe couplers or transformers of such a multiple arrangement issimultaneously varied in steps by means of a switch arrangement and inwhich the inductance within .thesteps is simultaneously varied.

'An object of our invention resides in a noveltuning control for anarrangement of the. above type and the method of constructionandarrangement of parts for the same. .A feature of our invention is theprovision ofa single control member for varying the inductance ofthesecondaries of a plurality of transformerssimultaneously in steps andfor simultaneously varying the inductance of the transformers, withinthe steps.

Another v feature of our invention is the provision of an operatingmember. in com bination with a single control member for actuatingthesame, and cam members secured to the said operating member which, inas sociation with a pair of arms,controlthe movements of the switcharrangement for varying the inductances of the transformers in steps andfor varying the inductances within the steps. 1

Another feature of the invention resides in V 5- 5 of Fig.2; 7 p ,7 Fig.6 is a perspective view of the cam the provision of apair ofcams on theoperating member which cooperate with apa-ir of arms whereby one of saidcams and its arm effect the simultaneous movement of switchesassociated, respectively,with the tapped inductances" of a plurality oftransformers to "positions corresponding to predetermined taps or zonesand, while said switchesremain in their predetermined positions, theother cam and its arm effect the movement'of the rotor elements of thetransformers to vary the. inductances within the predetermined zone. V I

elements of the transformers, and

The above featuresasfwell as others not.

particularly pointed out above will be more fully" described in theensuing specification and pointed out in the appended claims.

For. a more complete understanding of our invention reference may be hadto the accom panying drawings in which like reference characters in theseveral views denote like parts, and in which Fig. 1 is a frontelevation of the tuning control of our invention operatively associatedwith a multiple control arrangement and in which the front panel hasbeen removed to more clearly illustrate thermecha nism associatedtherewith;

Fig. 2 a top viewof Fig. 1; v Flg. 3 1 7 a sectional view along the l ne3 a of Fig. 2 looking in thedirectionoflthe arrowandillustratesclearlythe cam 'member and its associated'parts for controlling the movement ofthe switch mechanism by 1 successive steps tothe various zones' intowhich the secondaries of the transformers are divided; r v Fig. 4 is asectional view along the line 44: of Fig.2 looking in the direction ofthe arrow and clearly illustrates the cam member and its associatedparts for controlling the movements of the rotor elements of thetransformers to varythe inductances within the steps or zones; v v i pFig. 5 is a sectional view along the line which controls the movement ofthe switch mechanism associated with thetransformers; Fig. 7 is aperspective view of the cam which controls the movement of the rotorFig. shows a fragment of the indicato dial clearly illustrating the zonedivisions corresponding to'the switch positions and p the calibrationsof the dial within the ZOnes.

drawings, the tuning control of our invention, for the purpose ofillustration and description, is shown associated with a multiplecontrol arrangement for controlling the operation t an inductively tunedradio receiving circuit which comprises a plurality of transformers,portions of two of which are shown in the drawings. The transformers Tand T comprise the stator tubes 2 and 3 and the rotatable rotor tubes orelements 4 mounted Within the stator coils 2 and 3. One of the rotortubes shown clearly in F ig. 2. The stator tubes 2 and 3 supportsuitable windings 5 and are secured to panels 6 and 7 by means of screws8, and these panels 6 and 7 are in turn fixed to a suitable sub-base 9by means of brackets 10 which are secured respectively to the panels 6and 7 and subbase 9 by means of the screws 11.

The rotor elements 4 are. supported on a suitable rod 12 which may berotated to simultaneously rotate the rotor elements 4, 90 degrees oruntil their axes are at right angles to the axes of the stator coils 2and 3. The windings 5, supported on the stator tubes 2 and 3, are tappedand these taps 13 are connected to contacts 14 mounted on the panels 6and 7. The contacts 14, which are suitably secured to the respectivepanels 6 and 7 in arcs of circles, are adapted to be engaged by thedouble wiper arms W and l The wiper arms V and W each comprises wipers.15 and. 16, the free ends of which wipe over the opposite sides of thecontacting ends oi their respective groups of contacts 14.

The wipe-rs 15 and 16 of the respective wiper arms W and W are supportedby suit able wiper supporting members -17 which are rotatably supportedon the respective panels 6 and 7. Studs 18 and 19, secured to the wipersupporting members 17, extend forward from the panels 6 and 7 and havesecured to their respective ends arms 20 and 21. The free ends of thearms 20 and 21 pivot-ally support link members 22 and 23 provided withorifices 24 through which extends a connecting member or red 25 held inposition by means of the set screws :26. The rod 25 connects the arms 20and 21 associated respectively with the wipers W and W and, through themedium of the tuning control of my invention, the wipers W and V aremoved simultaneously step by step to engage successive contacts 14 oftheir respective groups.

Having described in general the multiple control arrangement with whichwe associate the tuning control of our invention, we will now describein detail the tuning control mechanism and its operation in associationwith the multiple control arrangement illustrated. The tuning controlcomprises a rotatable disk 27 having an integrally formed projecting hub28 with a central orifice 29 therethrough in which a sleeve 30 issecured by a drive fit. A pair of brackets 31 and 32,

secured to the sub-base 9 by means of the screws 33, are positioned onopposite sides of the disk 27 and are provided with aligned orifies 34which receive the reduced end portions 35 of the sleeve member 30 torotatahly support the disk 27. An angular bracket 36, secured to thesub-base 9, has secured to it a bearing block 37 provided with anorifice 38 through which a stub shaft 39 extends. A worm 40 is securedto the shaft 39 and meshes with the teeth 41 of a spiral gear cut in thecircumferential face 42 ot the disk 27 The shaft 39, which protrudesthrough an orifice in the front plate of the sub-base 9, supports asuitable operating knob (not shown), through the agency of which theshaft. 39 and worm 40 secured thereto are rotated. As the worm 40 mesheswith the spiral gear teeth 41 of the disk 27, the said disk 27 will berotated also for purposes which will presently be described.

A ring shaped member 43, secured to the face. 44 of the disk 27 by meansof the screws 45, provided with an integrally formed annular wall 46,the circumferential edge or u 47 of which is provided with a pluralityalternately long and short faces 48 and 49, arranged in steps, whichcooperate with an arm 50. The arm 50 is L shaped and is 'vivotallysecured to the ear 51 integral with the bracket 31 by means of a pivotscrew 52 and nut 53. A sleeve 54 on the pivot screw 52 spaces the arm 50from the bracket 31. A roller 55 supported on the arm 50 is pressed intoengagement with the faces 48 and 49 by rii of a spring 56 coiled aboutthe sleeve 54 with its one end 57 formed to engage the bracket 31'andits other end 58 formed to engage the arm 50. The tension of the spring56 is such as to force the roller 55 to the right, as seen in Fig. 1, tomaintain the roller in engagement with the faces 48 and 49 as the disk27 is rotated. A link 59 pivotally secured to the free end 60 of the arm50, is provided with an orifice 61 through which extends the rod 25. Aset screw 62 looks the rod 25 in link 59. .As the rod 25 is pivotallyconnected to arms 20 and 21, associated with wipers WV and W. as well asto arm 50, the said arms will all move together. The connection of thearm 50 to the rod 25 is for the purpose of controlling the step by stepmovement of the wipers and W over their respective groups of contacts 14as will be more fully hereinafter described.

An annular disk 63 is secured to the face 64 ot the disk 27 by thescrews 65. The peripheral edge of disk 63 is in the form of ascendingand descending cam faces 66 and 67 which cooperate with an arm 68pivotally secured to the bracket 32 by a pivot member 69. The free end70 of the arm 68 has pivotallysecured thereto one end of an arm 71, theother end of which is pivotally secured to an ear 72 formed integrallywith a plate member les ees 73'fixed to' a collar 74 securedon the rod12 by means of a set'screw 75. A coil spring 76, supported on the collar74, has one end 7 7 formed to engage an car 78 on 'the. collar 7 4"andits other end 79 formed to engage the roller 80, secured to the arm 68intermediate of its ends, in engagement with the cam faces 66. and 67 asthe member 27is rotated; As

the rod 12, which supports the rotor elements of the transformers,extends freely through a central orifice 81 in the sleeve 30, it isrotat-' able independently of the disk 27. Thus any movement of the arm68, caused by the cam faces 66 and 67 engaging the roller on the arm 68,will be transmitted'to the plate 73 and collar 74 .to which the saidplate 73 is secured to cause rotation of therodli) for purposes whichwill presently be described.

Having described in detail the mechanism 1 comprising the dial controlof our invention and its association with a multiple arrangement, wewill now describe its operation in conjunction with the inductivelytuned arrangement herein disclosed. By the present invention theinductances of the secondaries of thetran sformers T and Taresimultaneously varied in steps byjmcans of the above described switcharrangement and the inductances of said transformers are variedsimult-aneously between said steps through the medium of a singlecontrolrmember." With the wipers .W and W in engagement with the firstcontact 14 of their respective contact groups and'the rotor elements 4positioned as illustrated in Fig. 2, the rotation of the shaft 39 in aclockwise direction, as viewed in Fig. 1., will cause the. worm 40,secured thereto and whichis in mesh with the spiral gear teeth 41 on thedisk 27 to rotatethe said disk 27 in the direction of the arrows shownin Figs. 3 and 4. As before described, the taps from the secondaries ofthe transformers T and T are connected to the contacts 14,

adapted to be engaged by the respective wipers W and W. These taps orsteps may be considered as corresponding to zones and as there are sevencontacts in each group, each contact may therefore represent a zone.

With the arrangement previously dc scribed the movable inductance coilssupported on the rotor elements 4 may, be siniultaneously adjustedwithin'each step or zone. That is, the shaft 12- with the adjustableinductance coils thereon, will be rotated around and back each time awiper WV or W is in enqa genient with one ofthe contacts 14. As the disk27 rotates, the, ascending cam face 66 of the member 63, secured. to-thedisk 27,

engages the roller 80, secured to the arm 68, forcing the same to theright,as viewed in Fig. 4, This movement of'the arm 68 to the rightrotates'the plate 7 3 and collar 74 in a previously engaged.

.through an arc of approximately-90degrees or until theiraxcs are atright anglcs 'to. the axes of the stator tubes 2 and 3."This will varythe inductance within the zone corresponding to the contacts l4'engagedby the wipers \Vand V. f 1

' The member 4-3, secu ed to the face44of the disk 27, is also rotatedbut as the roller 55, secured to the arm 50, is in engagement with aneXtendedstraightface 48 of the member 4.3 at this time, thewipers lV-andW remain in engagement with the first contact 14 of each of theirrespective groups while the-rotor elenientst are being rotated 'as just' described.

As previously e:(plained,eachof'the seven divisions of the secondariesmay-be considered a zone representing a particularfrequency band. A"dial, c'omprisingfa' suitable strip ofcelluloid 85, is mounted on theannular shoulder SGintegra-lly formedon the face 44 of the disk 27.In-Fig. 8 is shown the calibrations on a portion'of the dial,corresponding 'to 'oneof saidzones As the disk 27 is rotated,the'wipe'rsW and Ware moved at intervals from one contact l4 t0 the nextand the inductances offlth etransformers are varied"betweenthe steps asdescribed above. At the same timethe dial 85' is moved sothat thecalibrations thereon corresponding to the successive zones aredisclosed:

Aszthe shaft li and 1clisk27'are rotated'to move the wipers W and 'W"from one zone to the neXt,,the instant that the rollerBQ on the g arm/68passes thefapen" 87 of the ascending cam face 66, theroller 55 on'the,arm 5 0-has finished'its travel along theext'ende'd face 48 otv themember 43 and is m ved downunder the influence of theJspring 56intoengagement with the short face49 of the-member 43. This.descending'step of the roller 55 permits the arm 50 to move to the rightas viewed in Fig. 1, and the wipers andW are also moved a correspondingdistanceto the right to place their centactmgemls in engagement with thenext contacts of their-frespective groups but still perniitthe wipers Wand WV to remain in engagement with "contacts As the disk 27 continuesto rotate, the roller8 0 on'thearni68 followstheqdescending cam face 670f the member 63 under the influence of the spring 76 and the armtjSis'now moved to the left,

as viewed in Fig. 4 to cause the rod l2, .sup'. porting the rotorelements 4 to be rotated in a reverse direction is againplace the axesof.

.the rotor elein ents4 parallel with the aXes of their associated statorelements 2' and This position is assumed byithe rotorelee inents 4 whenthe- 'roller 80 on the arm68'has reached the bottom 90 of the depressionbetween the ascending and descending cam faces 66 and 67. The instantthat the roller 80 on the arm 68 reaches the point 90, the roller 55 onthe arm has also reached the end of its travel along the short face 49and is moved under the influence of the spring 56 down into engagementwith the next extended face 48. The arm 50 now moves to the right asviewed in Fig. 1 to disengage the wipers W and W from the first contacts14 and leave them in engagement only with the next contacts 14 whichcorrespond to the next zone. During the time the rotor elements 4 arebeing moved back to their normal posi tions with their axes parallel tothe axes of the stator elements, the wipers \V and 1V remain inengagement with the contact corresponding to the zone they are about toleave and also the next contact in order to disconnect the apparatus bya short circuit during the restoring movement.

The continued rotation of the disk 27 will cause the next ascending camface 66 of the member 63 to force the arm 68 again to the right, asviewed in Fig. 4, thereby rotating the rotor elements 4 to vary theinductances within this step or zone as before described. During eachmovement of the arm 68, the wipers W and W remain in engagement with thecontacts 14 now engaged due to the roller engaging an extended face 48of the member 43 while the rotor elements 4 are being adjusted to varythe inductance within the zone corresponding to the position nowoccupied by the wipers W and W. This op eration will be repeated foreach contact 14 as the wipers W and W are moved from one extremeposition to the other.

It will be obvious that the shaft 39 may be rotated in either aclockwise or counterclockwise direction to select a zone and to vary theinductances within a selected zone, as the roller 55 on the arm 50remains in engagement with the extended cam face 48 of the member 43while the arm 68 moves to the right or left, under the influence of thecam face 66 or 67 of the member 43 to rotate the rotor elements 4 withinthe selected zone. When the shaft is rotated in a counterclock- Wisedirection, as viewed in Fig. 1, the operation will be the same asdescribed above except the movement of the parts will be in a do notwish to be limited to the exact structure shown but aim to cover allsuch changes and modifications as come within the spirit and scope ofthe appended claims.

Having described our invention, what we claim as new and desire tosecure by United States Letters Patent is:

1. In a device of the class described, a variable inductance device, azone switch for varying the inductance of said device by steps, a rotorelement for varying the inductance of said device between said steps, asingle actuating device and. mechanism interconnecting said actuatingdevice and said zone switch and rotor element, respectively, foroperating said zone switch and said rotor element in a predeterminedsequence, said rotor element operating to gradually increase or decreaserespectively the inductance as saic. actuating device is moved to causesaid zone switch to increase or decrease the inductance.

2. In a device of the class described, a variable inductance device, azone switch for varying the inductance of said device by steps, a rotorelement for increasing or decreasing the inductance of said devicebetween each stcp of said switch and the next, means for instantaneouslyreturning the said rotor element to its first position as the said zoneswitch moves from one position to the next succeeding position, a singleactuating device. and means interconnecting said actuating device withsaid zone switch and said rotor element, respectively, for effecting theoperation of said switch and element incident to the operation of saidactuating device.

3. In a device of the class described. a transformer comprisinga statorcoil and a rotor coil adjustably mounted adjacent thereto. taps fromsaid stator coil, contacts to which said taps are respectivelyconnected. a zone switch having a wiper arranged to traverse saidcontacts, a single actuating member, a pair of cam members carried bysaid actuating member and means interconnecting said cam members withsaid zone switch and with said rotor coil, respectively, for moving saidwiper intermittently from contact to contact to vary the inductance ofsaid transformer by steps and for moving said rotor coil to vary theinductance of said transformer be tween said steps, incident to theactuation of said actuating member.

4. In a device of the class described, a transformer comprising a statorcoil and a movable coil adjustably mounted adjacent thereto, taps fromsaid stator coil, :1 of contacts to which said taps are respective lyconnected, a zone switch, a wiper for said switch arranged to traversesaid contacts. a rotatable operating member, a pair of cam memberscarried by said operating member and means interconnecting said camincur bars with said zone switch and with said rotor coil,' respcavei i'for movingb said wiper intermittently from contact tocontact to varythejinductance ofsaid transformer by steps indfor moving saidmovableCOll to vary the novablecoil adjustably mounted adjacent thereto, tapsfrom said stator coil, series of contacts to which said taps? arerespectively'connected,azone switch, a wiperfor said switch arranged totraverse said con tacts, a rotatably mounted disk, a pair of cam memberscarried by said disk, a link member between one of id cam members andsaid zone switch, a link between the other of said cam members andsaid'movable coil, said cam members and links cooperating upon rotationof said disk to move said wiper intermittently from contact to contactto vary the inductance of said transformer by steps and to move saidmovable coil to vary the inductance ofsaid transformer between saidsteps.

6. In a device of the class described, a

transformer comprising a stator coil and'a rotor coil adjustably mountedwithin said stator coil, taps from said stator coil, a series ofcontacts to which said taps are respectively connected,a zone switch, awiper for said switch arranged to traverse said contacts a rotatablysupported disk, a pair of cam members carried by said disk, meansoperatively connecting one of said cam members to said zone switch,other means operatively connecting the other of said cam'members to saidrotor coil, said cam members and means cooperating, upon rotation ofsaid disk, to move said wiper intermittently from contact to contact tovary the inductance of said transformer by steps and to move said rotorcoil to vary the inductance of said transformer between said steps. i

7. In a device of the class described, a plurality of variableinductance devices, zone switches, one for each of saidinductancedevices for varying its inductance by steps, rotor elements,one for each of said inductance devices for increasing; or decreasingits inductance between each step and the next of its respective switch,means for instantaneously returning the said rotor elements to theirfirst position as the said zone switches move from one position to thenext succeeding position, a single actuating device, and meansinterconnecting said actuating device with said zone switchesand saidrotor elements, respectively, for effecting the operation of saidswitches and rotor elements in cident to the operation of said actuatingf device. 7 7

v8. In a device of the class described, a plurality of transformers eachcomprising a stator coil and movable coil adjustably mounted adjacentthereto, taps from each of said stator coils, a series of'contacts foreach of said stator coils to which its taps are respectively connected,zone switches, one for eachtransformer, a wiper for each switch spondingtransformer, a single actuating device and means connecting saidactuating device to said zone switches and said movable coils,respectively, for moving said wipers intermittently over said contactsto vary the inductances of said transformers-by steps and for movingsaid movable coils to vary the inductances of said transformers betweenI each of said steps and'the next.

9. In a device of the class'described, a. plu- 1:

rality of transformers, each comprising a stator coil and arotor'coil'adjustably mounted adjacent thereto, taps from each of saidstator coils, a series of contacts for each stator coil to which itstaps are respectively 1;

connected, wipers, one foreach transformer, arranged to traverse thecontacts'of the corresponding coil, a single operating member,

cam members carried by sa-idoperating member, means interconnecting oneof said cam members with said wipers tomove said wipers.

intermittently from contactto contact to'vary the inductances of saidtransformers by steps, and me ans interconnecting the other cam withsaid rotor coils for moving said rotor coils to vary the inductancesofsaid transformers between said,steps,'both of said vmeans being renderedoperativeincidentto the operation of said actuating device.

10. In a deviceof the'class described, a' plurality of transformers,each comprising a stator coil and a movablecoil 'adjustably mountedadjacent thereto, taps for each-of said stator coils, series ofcontacts, one for each stator coil to which its taps are respeca. tivelyconnected, wipers arranged to traverse said series of contacts,respectively, a rotatable operating member, a pair ofcam members carriedby said operating member'and means interconnecting said cam members withsaid wipers and said movable coils, respectively, for moving said wipersintermittently from contact to contact'to vary the inductances of saidtransformers by steps and for moving said movable coils to vary theinductancesof said transformers between said steps. 11. In a device ofthe class described, aplurality of transformers each comprising a statorcoil and a rotor coil'adjustably mounted within its associated statorcoil, taps from each of said stator coils, series ofcontacts, 7

one seriesfor each of said stator coils to which its taps arerespectively'connected, wipers arranged to traverse said series ofcontacts, respectively, a rotatably mounted disk, a pair of cammemberscarried'bysaid 1 disk, meansoperatively connecting one of 'saidcammembers to said'wipers, other means operatively connecting the otherofseidca-m members to said-rotor coils. said cammem-*-- arranged totraverse the contacts of the corre- 9 v bers and means cooperating, uponrotation of said disk, to move said wipers intermittently from contactto contact to vary the inductances of ,saidtransiormers by steps and tomoi e saidrotor coils to vary the inductances of saidtransformersbetween said steps.

12. In a deviceof the class described, a transformer comprising a statorcoil and a movable coil. adjustably mounted adjacent thereto, taps fromsaid stator coil, a series of contacts to which said taps arerespectively connected, a viper arranged to traverse said contacts, asingle operating member, a pair of cam members carried by said operatingmember, and means interconnecting said cam members with said wiper andsaid movable coil, respectively,cooperating incident to the operation ofsaid actuating member, to move said wiper intermittently from contact tocontact to vary the inductance of said transformer by stepsandto movesaid movable coil to vary the inductance of said transformer betweensaid steps and then restore it to its normal position, the wiper c mbeing formed to position said Wiper in bridge of two adjacent contactsduringthe restoring movement of saidmovable coil.

13. In a device ofthe class described, a transformer comprising a statorcoil and a rotor coil adj ustably mounted adjacent thereto, taps fromsaid stator coil, a series of contacts to which said taps arerespectively connected, a wiper arranged to traverse said contacts,rotatable operating member, a pair of cam members carried by saidoperating member, and means interconnecting said cam members with saidwiper and said rotor coil, respectively, cooperating incident to therotation of said operating member to move said wiper intermittently fromcontact to contact to vary the inductance of said transformer. by stepsand to move said rotor coil to vary the inductance of said transformerbetween said steps and then restore said rotor coil to its normalposition, the

wiper cam being .formed to position said' wiper in bridge of adjacentcontacts during the restoring movement of said rotor coil.

'14. In a device of the class described, a transformer comprising astator coil and a rotor coil adjustably mounted therein, taps from saidstator coil, a series of contacts to which said taps are respectivelyconnected, a wiper arranged totraverse said contacts, a rotatablysupported disk, a pair of cam members carried by said disk, meansoperatively connecting one of said cam members to said wiper andQtherineans operatively connecting the, otherot said cam members to saidrotor 0011, said cam members and associated means bemgarranged tocooperate upon rotation of sai disk, to-moVe said Wiperinterrnittentlyfrom contact to contact to vary the inductanceof'saidjtransformer by steps and torotate said rotor coil in'fonedirection to June, 1929/.

I GEORGE R. EATON.

MORRIS ROSE.

